Combined cable guide arm and torque control switch



J. D. RUSSELL 2,472,860 COMBINED CABLE GU IDE ARM AND TORQUE CONTROLSWITCH June 14, 1949.

Filed Sept. 2, 1944 INVENTOR ATTORNEY Patented June 14, 1949 ICEApplication September 2, 1944","Siial1N65552 53f6 40'Cla'ims. (01.191-12) This invention relates to cable guides, and more particularly'to'rta :combinedcable guide arm and torque controlswitch'for use onelectrically operated vehicles. supplied 'with. power through a cablewound'on a reel carriedby the vehicle.

While myinvention may be used onany'vehicle having a cablereeljit is.especially adapted for use in connectionwith'a shuttle. car ofv thegeneral character disclosedin.UL'SJLetters Patent No.2,325,731,.issued'August 3', 1943. Such cars, which are'now ingeneraluse in the mining fields of thisecountr'y, are used to. perform thesecondary haulage in the mine, and shuttle back and forthbetween themirieralproducing area and a discharge .stationiin transporting theminerals from theriworkingwfaceito the.main line haulage f.the mine..Th'ecars areisuppliediwith power throughraecable onenendi of .which isattached to a constant source of power, and'is anchored at. .a vLpointWnear the discharge station. The cable isLwound on areal driven byasuitable motor whichisarmnged-to permit the reel to .unwindorpayoutrthecableas the car moves away fromthe point:wherethecableisanchored, and to wind up or. reellinthe cable as the car movesin. .themppositedirection. The distance of travelof vehiclesbf. thistype is controlledby the length of cable-woundon lthe reel,anclthe carscannotreadily runlpasti-the pointwwhere the cable is anchoredwithoutvdanger of-damaging the cable.

The principalieobjectmof this inventionris to providemeansfor-materially increasing the range of travelof an electricallyoperatedwehicle supplied with power-throughiaicablez-wound-on-a reel carried bythe-vehicle 2wi-thoutincreasing the length of the-cable:

Another ObjeGt'iS: to-arprovide. 1a a cable guide which'will guidethe'cable astitis.payed=out and reeled in in such: amannerthat danger ofthe vehicles running; over fand= damaging ":the-fcable isreducedtmaminimum:

Another object isnto providea combined cable guide arm and control:switchdorthe torque motor operating a-cable=reel-tthat willcause therequired torque to be applied to the cable reelrwhen the cable is beinpicked up, and will suitably reduce: thefamountof. torque: of: themotorwhen the'cable is beingepayedbut.

A further ObjB'CViSaTbO provide e a-torque control switch for-the motor.operatinganablereel-which will control: the-:amountof 5 torque appliedto-the cable reel in accordancefwith the erelative-apositiom of:tbuvehicle: to-itheeanchor "point oi the cab1e,--and=- will-1automatically;iproviderthemaximum-torque when the-vehicle isapproaching the anchor point; and 'a suitably==reduced torque as thevehicle moves away. from-theanchor point, whereby --the--vehicle mayrun-past the anchor point and its range of travel be -materiallyincreased."

These and other-objects which will hereinafter be made apparent tothoseskilled in this particularartare accomplished-by means of thisinventiomone embodiment of which is described in i the followingspecification and illustrated in the accompanying drawing, wherein:

Fig.- 1 is a'perspecti've view ofmy improvedcombined cable guide *armand torque control switch mounted on the forwardend'ofashuttle car;

Fig. 2 "is-awbottomplanview-'of the control switch with thecoverremovedf.

Fig.- 3 is a'topplanyiew'of the cable guide arm and torquecontrol'switch'with thesguide arm turnedto lay the cable along the sideof the car;

Fig. 4 is adiagramdllustratingone method of wiring the controlswitchwiththe controls of the vehicle;

Fig. 5 is adiagrammatic view illustrating the range ofoperationcfashuttle car having a cable uide arm" and'torque control'swit'ch made in.accordance with my invention:

Referring first to Fig.5 of the drawings, l0 illustrates'an electricallyoperatedshuttle car of the type used extensively'zto perform thesecondary' haulage'in mining operations, which .is adapted totravebbackiandforth; in .the mine chamber 'A between the working face Band the haulage entryC. The car: lll'is suppliedrwith power through acable H connected and anchoredatl 2"toi.a.suitable' source of electricpower. The cable H is -normallyj-reeledon a suitable motor driven cable.reel,not shown,l,carried by the shuttle car lllgwhichjisde'signed towind up or reel .in the cable as "that car approaches the anchor point12,";and lto payout or unreel the cable asthe car movesawayifromtheanchor point.

The amount of .pulllon .the cable .is desirably greater when :the cablesis-picked 'up than. it is whenithencable is'beihg payedout, andtoisecure this differencein pullliand permitj the, carto travel pasttheanchorup'oint .-.l 2 in either. direction,.I employ ,al torquemoton. M;.(Fig.; 4) for driving the cablereel, and providemeansiforcontrollingthe torque of theumotor, In, order to reducel the torque ofv.the -motor-M a-stthei cart I il'zpasses the anchor :point I2 whiletraveling. from -A-to C (or :vice i versa, I; iprovide-saoswinaina:cable guide armdl ll ig. 1) which is adaptedrtot-be turned 3 by thecable as the car passes the point l2, and operate a switch reducing thetorque on the motor M as will hereinafter be more fully explained.

The cable guide arm it is provided with cable uide rollers E la at itsforward end, and is pivotally mounted on a vertical pin i6 journaled ina bracket if on the forward end of the shuttle car it. Guide arm it isconnected by a rod It witl'i a lever 59 secured to a vertical shaft Elljournaled in a housing 2i which is bolted to the frame or the shuttlecar ill. The shaft 2t carries a revolvable drum 22 of the switch it. Thedrum 25.; is adapted to engage two of a series of three contact fingers23, 2d, and 25, which are connected with the forward and reverseswitches controlling the operation of the car if].

Assuming that the shuttle car it is in the full line position shown inFig, 5 and it is desired to travelfroni the working face B to the entryC. The forward operating switch 3i) (Fig. 4) is manually closed,energizing the forward contactor F, closing the circuit 3%, and powerfrom the conductors 32 and 33 is delivered to, the main motors. notshown, of the shuttle car it. When the car is'in this position at theworking face, the cable li lies directly in the path that the car willtake, and the guide arm it extends out toward the front of the car. Withthe guide arm Hi in this position, the drum 2?. of the switch it is heldin engagement with the contacts and and current therefore flows throughthe lead dd, switch iii, and wire 35, and energizes the contactor T andcloses the circuit 36, and thereby shunts the major part of theresistance 33' which has been in series with the armature of the torquemotor M, which, as will be hereinafter explained, operates at itsmaximum torque when said shunting circuit is closed, and Xe-rts themaximum pull to wind up the cable. It will be observed that the motor Mwas supplied with current by the conductors t2 and 33 even before thecircuit 3i is closed, though with the full resistance 3'5 in series withits armature. This means that the cable was maintained under suitabletension even before the car commenced to move.

As the car it passes the anchor point 12, the cable it causes the guidearm is to swing outwardly and project from the side of the car so thatthe cable will be payed out in a path parallel to the path of travel ofthe car. As the guide arm it is swung by the cableto its side position,the lever 53 and the shaft 2i] secured thereto are turned, andthe switchdrum 2.2 is moved into contact with the fingers 23 and 25, and thecircuit between the leads 3d and 35 is broken, which deenergizesthecontactor T and opens the circuit Current then flows from the leads 32and 33 through the resistor or resistance element 31 arranged in serieswith the armature of the motor M, which reduces the torque of the motorto. the required value. As the car proceeds toward the entry C, thecable is payed out against the torque of the motor M, and the resistor37 is of such value that the torque of the motor is only sufficient toapply the proper amount of tension in the cable as it is being payed outfrom the cable reel. the contactor It, shutting off the power to thetraction motors. It will be noted that this will not cut off currentsupply to the motor 1V1.

When it is desired to drive the vehicle in the opposite direction ortoward the working face 33, the reverse switch 38 is closed, which ener-The car is stopped by opening gizes the reverse controller R. On theenergizing of the contactor R, the power circuit 39 is closed andcurrent flows from the lead 32 through the power circuit 39 to themotors of the shuttle car iii, and the car starts to travel toward theworking face. Upon the closing of the switch 33, a circuit is alsoestablished through the lead lil, switch parts 25, 22, and .23, and lead3-5, which energizes the contactor T and closes the circuit lit. Uponthe closing of the circuit 36, the major portion of the resistor 3'? isshunted out, and the motor M is again caused to operate at its ma:-:imumtorque to wind up the cable previously paid out as the car moves towardthe working face.

As the car moves past the anchor point 12 on its return journey, theguide arm i l is returned to its original position by action of thecable, and the drum 22 is moved from engagement with contact fingers 23and 25 into contact with the fingers 7:3 and 2t. This movement of theguide arm deenergizes the contactor T and opens the circuit 36, andagain the full value of the resistor ill is placed in series with thearmature of themotor M and the torque is reduced to the minimum, and thecable is permitted to pay out as the car proceeds to its originalposition where the cycle of operation is completed.

It should be noted that when the drum .22 is in engagement with thefingers 232 l, the contactor is in parallel with the forward contactorF, and when the drum contacts fingers 23-45, the contactor T is inparallel with the reverse contactor B. As a result of this method ofwiring, when the forward contactor F is energized and the switch part 22is in contact with fingers 23-24, the contactor T will also beenergized.

Upon the turning of the guide arm, however, while the forward contactorF is still energized, the switch drum 22 will be turned into contactwith the fingers .23 and 24, which deenergizes the contactor T andplaces it in parallel with the reverse contactor R, so that upon theenergization of the reverse contactor, the contactor T will also beenergized. Thus, regardless of the direction of travel of the car or ofits position relative to the anchor point 12, the proper torque will beapplied to the motor to wind in or pay out the cable whenever the car isstarted.

It should also be noted that with my improved guide arm the cable islaid down in a path parallel to the path of travel of the car when thecar is moving forward beyond the anchor point, and consequently thedanger of damaging the cable by its being run over by the car ismaterially reduced. To prevent any sharp bends in the cable I l as it ispayed out or reeled in, I mount a pulley 42 above the switch l5 whichguides the cable from the rollers I la on the end of the arm id toanother set of guide rollers 43 mounted on the side of the vehicle.

While I have described one embodiment of my invention, it is understoodthat certain additions, modifications, omissions, and alterations may bemade therein without departing from the spirit of my invention or thescope of the appended claims.

I claim:

1. The combination with an electrically driven shuttle car having acable reel and a motor for driving said cable reel, a contactor forcontrolling the forward movement of said car, a contactor forcontrolling the reverse movement of said car, a resistor in series withthe armature of said motor. means for shunting out the major portion ofsaid resistor wheneither of said forward and reverse contactors isenergized, and-meansifor reinserting the full value ofsaidiresistoriwhilemaintaining one of said contactorsenergized.

2. The combination with an electrically oper ated vehicle suppliedwithpowen through acable wound on a reel carried-bythervehicle; ofanon-.- tactor for controlling the forward movementol said vehicle, acontactor forcontrolling the freverse movement of said vehicle, a torquemotor-for driving said cable reel, .meansresponsi-ve to the energizationof either ofsa'id contactors foropere ating said motor at itsmaximumxtorque, and means for reducing. :theutorquer-ofisaid motorwithout deenergizing said contactor.

3. The combination with an electrically operatedsvehicle suppliedwithpower through aicable wound on. a reelacarriedaiby'zsaid'vehicle-.acomprising .a forward contactor; at reverseicontactor, atorque motor for drivingzsaidmable 'reel, aresistance element inseries'withithe'armature of said .motor, means responsive :to .the--.energization of either of said contactors: for. shuntingaout. themajor portion of said resistance element, and means for neutralizingsaid lastimentioned means while maintainingthe venergivatiomof saidcontactor.

4. The combinatiomwithanzelectrically operated vehicle suppliedwithpowerythrough a cable wound on a reel and .carriedby-said;vehicle,.comeprising a forward contactor, a :reverse-contactor, a torque motor fordrivingsaidcable reel, a resistance element in series with. the armatureof said motor, a contactor normally in parallel'with one 'of saidcontactors and adaptedomenergization to shunt out said resistance:element,.and means for deenergizingsaidlast mentioned cone tactor andplacing it in parallel with theotherof said contactors.

5. The combination with anelectricallyoperatedvehicle supplied withpower through-a cable wound on a reel carried by saidlvehicle comprisinga torque motor for operatingsaidreel, aacable guide arm pivoted on saidvehicle adapted to lay said cable in a line parallel to thelineof travelof the vehicle, and means responsive to the turning of said arm forvarying the torque produced by said motor.

6. The combination with an-electrically=operated vehicle suppliedwithpower througha cable wound on a reel carried by said vehiclecomprising a torque motor for operating saidcable reel, aresistanceelementin series :withsaid motor, a contactor adapted on energization toshuntiout said resistance element to permit said -.-motor to develop themaximum torque,=a swivel cable guide arm, and means responsive tothe-movement of said arm for deenergizingsaid contactor and reducingthetorque of saidmotor.

7. The combination with:anelectricallyoperated vehiclesupplied-withpower through-acable wound on a reel carried by saidvehiclecomprising a motor for operating said cablereel, aresistor inseries with said motor, means-for shunting out saidresistor whensaidcable: is being wound up'to operate said motor at :therequiredtorque and means for automatically reinsertingsaidresistor,while electrical operation of said :vehicle in the same direction ismaintained,. to cause said motor to operate at minimumtorque-es thecable is being payed out.

8. Apparatus oi the characterdescribe'd comprising a pivotallymountedarm, aacabl'e guide carried-on the forward endvof' sai'd arm; said "ambeing adapted to be turnedrsbyq the pull. oft-the cable passingthroughsaid guide betweenpositions in-which said cable extends inrelativelysopposite directions, a magnetic contactor, andz-aswitchactuated by the movement of said armafor .0011!- trolling theenergization of saidscontactorand having circuit closing positions ateachlotitstopa posite extremes of turning movement.

9. The combination with a cable reelandrmeans for transporting the same,of a torque :motor'ior operating said reel, a motor circuit, aresistorzin said circuit in. series with the armatureizofi'said motor,means for shunting out said resistorztoiinzcrease the torque of saidmotor'whenxsaid. cable is being reeled in during transportation:ofnsai'd reel in a given direction, and means: for automaticallyreinserting said resistor in. themotor circuit when said cable is :payedoutrdurlngxcontinued transportation of said reel. in. the samedirection.

10. In combination with an electric-"motor.- driven vehicle suppliedwith power through a cable Wound on a reel carried by the vehicle,toi3.100113- tactor for controlling the forward movementcof said vehicle, acontactor controlling the rearward movement of said vehicle, a motor fordriving said cable reel, a resistance element inseriesxwith the armatureof said motor, a contactor normally in parallel with either the forwardonreverse contactors and adapted to be energized whenthe contactor inparallel therewith is energized ;to shunt out said resistance elementandincrease the torque of said motor, and means. for deener:- gizingsaid last mentioned contactor'to reestablish the full value of saidresistor to reduce the torque of said motor and for placing saidcontactor: in parallel with the cleenergized-forward-or reversecontactor.

11. The combination with a vehiclehavingza cable reel mounted thereon,with the powenreceiving end of said cable anchored intermediate the pathof travel of said vehicle, of a torque motor for operating said cablereel, meansfor operating said motor at maximum torque when said vehicleis approaching the anchor point of said cable, and means for reducingthe torque of said-motor to a lower value as said vehicle moves pastsaid :cable anchor point.

12. The combination witha vehicle. having a cable reel mounted thereon,with the power-receiving end of said cable anchored intermediate thepath of travel of said vehicle, of a torque motor for operating saidcable reel, means for operating said motor at maximumtorquewhen saidvehicle is approaching the anchor "point. :of said cable, and meansresponsive to the'sidezpull of said cable 'for reducing the torque of;said inc.- tor to the minimum as said vehiclemovespastsaid cable anchorpoint.

13. The combination with a vehicle. haVl'ngxa cable reel mounted thereonwiththepowerure ceiving end of said cable anchored ata pointalong thepath of travel of said vehicle, meansfordriving said cable reel at therequiredtorquento wind up said cable as the car approaches the anchorpoint, and means for operating the cable reelat reduced torque to payout said cable as thecar moves past the anchor point.

14. The combination with a vehicle-having a cable reel mountedthereon-with the power receiving end of the cable anchored-at apoint'along the length of travel of said vehicle, of means for drivingsaid cable reel at the required-torque to pick up said cable as the carapproachesthe anchor point, means responsive to the movementof saidcable for driving said cable reel -at a reduced torque as said vehiclemoves away from' -said anchor point to pay out said cable, and means forlaying said cable in a path substantially parallel to the path of travelof said car.

15. The combination with a vehicle having a cable reel mounted thereonwith the power re ceiving end of the cable anchored at a pointintermediate of the range of travel of the vehicle, a swingable cableguide arm, means for driving said cable reel at the torque required towind up said cable as the vehicle approaches the anchor point, and meansresponsive to swinging of said guide arm for reducing the torque of saidreel driving means to pay out the cable as the car moves away from theanchor point, said guide arm being ar ranged to lay the cable to theside of the vehicle when the vehicle is moving in one direction awayfrom the anchor point.

16. A control system for a motor operating a cable reel on a vehicle fora cable supplying elec trical energy to the vehicle from an extraneoussource comprising, means operable to vary the torque of the cable reelmotor, and means responsive to change in the angle of the cable, as thelatter extends away from the vehicle, to the path of reel movementoperable to control the torque varying means.

17. In a control system for a torque motor operatively connected to acable reel for a power cable supplying electrical energy from anextraneous source to a vehicle, switch means operable to vary thearmature current of the torque motor, and control means responsive tochange in the angle of the cable, as the latter extends away from thevehicle, to the path of reel movement operable to effect operation ofthe switch means.

18. A control system for a cable reel motor on a vehicle having a cablefor supplying electrical energy through a controller to a motor foroperating the vehicle comprising, switch means operable to vary thetorque of the reel motor, a control switch operable to differentpositions in response to changes in the angular relation of the cable tothe reel, control means associated with the controller, and circuitmeans connecting the control means and the control switch for operatingthe switch means selectively in accordance with the direction of motionof the vehicle relative to the point of attachment of the cable to asource of electrical energy.

19. A control system for a motor operating a cable reel on a vehiclehaving a main driving motor disposed to be energized from a source ofelectrical energy through a cable carried by the reel comprising,circuit means connecting the cable reel motor to the cable, controlmeans operable to vary the impedance of the circuit means, and means forefiecting operation of the control means whenever the vehicle passes thepoint of attachment of the cable to the source including a movable armactuated by the cable in accordance with a change in the angularrelation of the cable to the reel.

20. A control system for a motor operating a reel for a cable disposedto be attached to a source of electrical energy for supplying electricalenergy to a driving motor of a vehicle through a controller comprising,control means operable to change the torque of the reel motor, meansassociated with the controller operable to reduce the torque of the reelmotor when the vehicle moves away from the point of attachment of thecable to the source on one side thereof, and means operable to reducethe torque of the reel motor as the vehicle moves away from the one sideof the point of attachment to the, other side.

21. The combination in a control system for a motor operating a reelmounted upon a vehicle for carrying a cable disposed to be attached to asource of electrical energy for supplying electrical energy to thevehicle, of a control impedance, switch means for connecting theimpedance in series circuit relation with the reel motor, and controlmeans including a movable switch arm operable to different positionsdepending upon which side of the point of attachment of the cable thevehicle is operating for effecting operation of the switch means as thevehicle passes the point of attachment of the cable to the source 22. Ina control system for a motor operating a cable reel on a. vehicle forsupplying electrical energy to the vehicle from a power source, incombination, control means operable to vary the torque of the reelmotor, and a pivotal arm actuable to different positions to effectoperation of the switch means, said arm having a guide member forreceiving the cable and being actuable to different positions dependingon changes in the angular relation of the cable with the reel as thevehicle moves from one side of the point of attachment of the cable tothe other.

23. In combination, a reel mounted on a vehicle and carrying a cabledisposed to be attached to a source of electrical energy for supplyingelectrical energy to the vehicle, a driving motor for operating thevehicle, a reel motor for operating the reel, control means operable tovary the torque of the reel motor, a controller for the vehicle drivingmotor having contact means operatively associated therewith forefiecting operation of said control means Whenever the vehicle drivingmotor is reversed, and additional control means responsive to theposition of the vehicle relative to the point of attachment of the cableto the source for operating the control means whenever the vehiclepasses the point of attachment, thereby to maintain a substantiallyconstant tension on the cable.

24.. In a cable reel system, in combination, a cable reel having anoperating motor, control means operable to increase the torque of thereel motor, switch means operable to effect operation of the controlmeans, and means comprising a pivotal arm having a guide for receivingthe cable adjacent the free end for eifecting operation of the switchmeans whenever the vehicle passes the point of attachment of the cableand the cable changes its angular relation with the reel.

25. A control system for a motor operating a cable reel on a vehiclehaving a driving motor energized through the cable from a source ofelectrical energy and control means for the motor comprising, a controlresistor connected in series circuit relation with the reel motor,switch means operable to shunt a portion of the resistor, circuit meansconnected between the control means and the source for effectingoperation of the switch means whenever the direction of travel of thevehicle is changed by the control means, and additional control meansincluding a switch operated in response to passage of the vehicle pastthe point of attachment of the cable associated with the control meansfor operating the circuit means whenever the vehicle passes the point ofattachment.

26. A control system for a motor operating a cable reel on a vehiclehaving a driving motor energized under the control of a controllerthrough a cable carried on the reel and connected to a source ofelectrical energy comprisa control; resistor-s connected in; series..cir-

erated vehicle :sl-lDpl-ied-with power-through a cable woundon a reel:carried by the vehicle, of a contactor for controlling theforwardxmovement of the vehicle, a contactor for controlling the reversemovement of the vehicle, a torque motor for driving said cable reel,means for controlling .the torque exerted by said torq-ue .motorincluding parallel current paths-one including a resistance and theotherincluding a switch for shunting said resistance," and means responsiveto the energization of either; of said two contactors .for:.--eflecting.closure-oft said switch to shunt said resistance.

28. The combinationwith ;ani:electrically operated vehicle suppliedwith:power?througha cable wound: ona reel carried by thezvehicle; of acontactor for controlling the forward movement of the vehicle, acontactor for controlling the reverse movement of the vehicle, a torquemotor for driving said cable reel, means for controlling the torqueexerted by said torque motor including parallel current paths oneincluding a resistance and the other including a switch for shuntingsaid resistance, means responsive to the energization of either of saidtwo contactors for effecting closure of said switch to shunt saidresistance, and means controlled by the direction in which said cableextends from said reel for effecting opening of said switch while thecontactor whose closing caused closures of said switch remains closed.

29. The combination with an electrically operated vehicle supplied withpower through a cable wound on a reel carried by said vehicle,comprising a torque motor for operating said cable reel, a resistanceelement connected with said motor to effect the exertion by the latterof a low torque, a contactor operable to shunt out said resistanceelement to permit said motor to develop a higher torque, means forguiding said cable in relatively opposite directions from said vehiclelongitudinally of the latter, and means controlled by said cable guidingmeans for deenergizing said contactor to effect reduction of the torqueof the motor when the direction in which the cable extends from thevehicleis reversed.

30. Apparatus of the character described comprising a pivotally mountedarm, a cable guide carried on the free end of said arm, means forsupporting said arm for turning by the pull of the cable passing throughsaid guide, a magnetic contactor, and a switch actuated by the movementof said arm for establishing, in opposite extreme positions of said arm,different circuits for controlling the energization of said contactor.

31. The combination with a vehicle having a cable reel mounted thereon,with the power receiving end of said cable anchored between the ends ofthe path of travel of the vehicle, of means operatively connected withsaid cable reel for rotating the same in a winding in direction andresisting the rotation thereof in anunwinding'direction, means forcausing said last mentioned means to exert a maximumtorque when saidvehicle is approaching-the anchor point of said cable, and means forreducingthe torque exerted to a lower value as said vehicle 'moves pastsaid cable anchor point.

32. The combination with a vehicle having a ,cable reel mounted thereon,with the power receivingend- Of said cable anchored at a point along thepath of travel of said vehicle, means for driving said cable reel at'therequired torque to wind up-said cable as the vehicle approaches theanchor point, and means for automatically reducing the torque exertedby. said last mentioned means when said'vehicle isoperatingin the samedirection beyond said anchor point, whereby said cable is maintainedunder a lower tension during the paying out .thereof.

. 33. A control system for a'rnotor operating a cable-reel on a vehiclefor a cable supplying-electrical energy-to the vehicle comprising meansoperable to .vary thetorqueof the cable reel motor, and means responsiveto the angular direction relative'to'the vehicle of theportion of thecable extending from the Vehicle to the'point'of convnection of thecable, operable to-control the torque varying: means.

"34, Inacontrol system for a torque-motor'operatively 'connectedto acable reel for a power cable supplying electrical energy to a vehicle,switch means operable to vary the armature current of the torque motor,and control means for effecting operation of said switch means,responsive to that change in the angular relation in generallyhorizontal planes to the vehicle of the portion of the cable extendingoff from the vehicle which occurs, by virtue of change in position ofthe vehicle, when a change from shortening to lengthening of saidportion of said cable is necessary.

35. In a control system for a torque motor operatively connected to acable reel for a power cable supplying electrical energy to a vehicle,switch means operable to vary the armature current of the torque motor,and control means for effecting operation of said switch means,responsive to that change in the angular relation in generallyhorizontal planes to the reel of the portion of the cable extending offfrom the reel which occurs, by virtue of change in position of thevehicle, when a change from shortening to lengthening of said portion ofsaid cable is necessary.

36. The combination with a vehicle having a reel rotatably supportedthereon and a flexible conductor secured at one end to said reel andhaving the power receiving end thereof anchored at a point relative towhich said vehicle moves and at least a portion of the cable so disposedthat as the vehicle travels along a working path there is a changebetween winding and unwinding operations, means for driving said reel atthe required torque to wind up the cable as the vehicle moves in adirection to introduce slack in the cable, and means for automaticallyreducing the torque exerted by said last mentioned means when saidvehicle continues to operate in the same direction but in a portion ofits travel when unreeling of the cable is necessary, whereby said cableis maintained under a lower tension during the unreeling thereof.

3'7. Apparatus of the character described comprising a pivotally mountedarm, a cable guide carried on the free end of said arm, means forsupporting said arm for turning by the pull of the cable passing throughsaid guide, a magnetic contactor, switches Selectively closable and aswitch actuated by the movement of said arm for establishing, inopposite extreme positions of said arm, difierent circuits, respectivelycontaining difierent ones of said selectively closable switches, forcontrolling the energization of said contactor.

38. The combination with a vehicle having a cable reel mounted thereonwith the power receiving end of the cable at a stationary point and withsaid vehicle moving in a path such that the portion of the cable whichleads to the vehicle is in certain portions of said path at one side ofa position perpendicular to said path and at other points in said pathat the opposite side of such a perpendicular, means for driving saidcable reel at the required torque to wind up the cable as the vehicleoperates towards the position at which such perpendicularity exists, andmeans for automatically reducing the torque exerted by said drivingmeans when said vehicle is operating in the same direction but at theother side of said position at which such perpendicularity exists,whereby said cable is maintained under a lower tension during the payingout thereof than during its winding in.

39. A control system for a motor operating a cable reel on a vehicle fora cable supplying electrical energy from an extraneous source to thevehicle comprising, means operable to vary the 12 torque of the cablereel motor, and means governed by the angular direction in generallyhorizontal planes of the cable, as the latter extends away from thevehicle, relative to the path of reel movement operable to control thetorque varying means.

40. In a control system for a torque motor operatively connected to acable reel for a power cable supplying electrical energy from anextraneous source to a vehicle, switch means operable to vary thearmature current of the torque motor, and control means responsive tochange, produced by vehicle movement, in the angle of the cable, ingenerally-horizontal planes, as the latter extends away from thevehicle, to the path of reel movement operable to efiect operation ofthe switch means.

JOHN D. RUSSELL.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 1,467,253 Sharpsteen Sept. 4,1923 1,765,547 Sloane June 24, 1930 1,843,743 Shafier Feb. 2, 19321,857,817 McCann May 10, 1932 2,359,123 Krapf Sept. 26, 1944

